10. Gaydar
The premiere episode of Season 3, Gay Witch Hunt, had Dwight learning that Oscar was gay and trying to find out who else in the office was. It was obvious through everything they said that both him and Michael were completely ignorant about gay people. They call Jim to ask about the ‘gaydar’ machine that he once mentioned. Jim plays along, and says it’s sold out. But he uses this opportunity to make one and send it to Dwight, who then tests it out on Oscar successfully as the machine beeps. Dwight is happy the machine works, only for the machine to start beeping when it’s in front of Dwight’s crotch. A look of horror passes through Dwight’s face as he realizes he might be gay. Half the time Dwight’s face alone is enough to make a prank worth it.
9. Magic Beans
In Season 7’s Garage Sale, Dwight trades his way through to get the most valuable item. Jim, as expected, takes this opportunity to prank Dwight. He places a packet of beans, “Professor Copperfield’s Miracle Legumes” on his table and pretends like it got there by itself. He claims to have gotten it from Jamaica and implies that they are magic beans. Dwight doesn’t believe him at first. But later on it appears on the table once again. Jim throws it on the floor to step on and destroy it in front of Dwight. And once again, it shows up on his table by itself.
This time, Dwight is walking with a telescope that he traded his way to get. Dwight is sold on the beans once he sees them on the table again and reluctantly trades his telescope for it. Jim walks away with a telescope, while Dwight proudly talks about how he started with a thumb tack and traded his way to the “most valuable thing” there, those magic beans. And there’s that look on his face when he realizes how stupid he sounds. Well done, Jim.
8. A.A.R.M.
In Season 9’s A.A.R.M., Jim (who is Assistant to the Regional Manager) convinces manager Dwight that he needs his own Assistant. He conducts a series of tests to find someone who can be his assistant, but these tests are designed such that only one person can win it: Dwight himself. And he does. The best part is, Dwight loves being Assistant to Jim, because he believes only he is capable of being that person. So in effect, Jim is now manager because whatever Dwight makes him do, he can just give it back to Dwight and make him do it because he’s both Jim’s boss and his assistant. It’s an insanely clever prank that’s made better when we see Jim actually make Dwight do his work for him.